Ecology of northern long-eared bats (Myotis septentrionalis) in a coastal setting after the introduction of White-nose Syndrome

Northern long-eared bat (Myotis septentrionalis) populations have declined sharply in recent years due to the introduction and rapid spread of White-nose Syndrome. This has prompted an urgent need for a greater understanding of their natural history in order to support the conservation of extant populations, particularly where forested day-roost and foraging habitats are being fragmented by development. Prior to 2006, with other Myotis species on the endangered species list, northern long-eared bats were understudied. In recent years, with the pressing concern to document the ecology of all cave bats affected by White-nose Syndrome on the landscape, researchers have now prioritized northern long-eared bat habitat needs, day-roost use, social dynamics, and barriers to gene flow. A relatively new discovery has been the numerous coastal populations that occur in smaller forest patches often surrounded by anthropogenic development. The goal of my research is to aid in informing future monitoring and management protocols that are specific to northern long-eared bats, particularly as they may shift from Threatened to Endangered under the Endangered Species Act. The chapters of this dissertation explore (1) similarities and differences between coastal and more documented upland habitat associations for populations of northern long-eared bats throughout the summer months through the use of acoustic detectors; (2) relationships between acoustic activity patterns and weather on an hourly basis for several bat species on Long Island, New York; and (3–4) day-roost characteristics and social network dynamics of a coastal northern long-eared bat maternity colony on Long Island, New York. I found that northern long-eared bat colonies have larger spatial footprints in – and a moderate tolerance for – forests in anthropogenically-developed areas than previously believed, though many natural history aspects of the bat were similar among coastal and interior populations. Installation of artificial day-roost structures such as bat boxes would likely be used and highly beneficial to colonies in these conditions, particularly to offset the deleterious effects of stochastic disturbance events on day-roost availability and to support social cohesion (and, by extension, reproductive success) for coastal maternity colonies. Additionally, I found that acoustic activity increased in riparian areas, or at sites closer to water features, and as proportion of forest coverage increased at a broad scale. However, immediately around the detector this relationship was reversed. Taken together, this demonstrates that riparian corridors, water features, and forest structural heterogeneity should explicitly be included in management guidelines.